Stable hydrogen-peroxid solution.



tINrrED STATES PATENT OFFICE.

, OTTO LIEFKNECHT, FRANKFORT-ON-THE- MAIN, GERMANY, ASSTGNOR TO ROESSLER I is a specification,

AND I-IASSLACHER CHEMICAL 60., OF NEW YORK, N.

Specification of Letters m Y.. A conronarron ornnw STABLE HYDROGEN-PEROXID SOLUTION.

Patented May 7, 1912'.

No Drawing. Original application filedNovember 18, 1908, Serial No. 463,192. Divided and this application filed March 1, 1911. Serial No. 611,587.

T0 on! whom it may concern:

Be it known that'I, OTTO LIEBKNECHT, a subject ofthe Emperor of Germany, and a resident of Frankfort-on-the-Main, Germany, have invented a new and useful Stable Hydrogen PeroXid, of which the following the same being a division of my application, Serial No. 463,192, filed November 18, 1908. I

This invention relates to a stable hydrogen peroxid. i

Heretofore strong mineral acids have been chiefly used in order to render hydrogen peroxid solutions stable, for instance, a certain quantity of phosphoric acid has been added to the hydrogen peroxid. The stability thus obtained is however of limited duration, as after a short time appreciable losses of active oxygen take place. The addition of mineral acid has, however, been conv sidered necessary, as without it a quicker decomposition takes place. The action of the mineral acid is accounted for by thestronger electrolytic dissociation of the mineral acid, which lessens the dissociation of the exceptionally weak acid hydrogen p'eroxid and thus prevents decomposition. e

The comparatively low degree of stability of the present hydrogen peroxid solutions, even with the addition of mineral acids, has been commercially a great drawback and medically the use of such acid hydrogen peroxid solutions isgreatly retarded on ac- V count of causing irrltation. There is also in the market 30% chemically pure hydrogen peroxid which, however, in order to preserve its stability, must be kept in parafiined bottles. This product has to be diluted before using and then undergoes the quick decomposition hereinabovedescribed.

The object of the invention is to overcome the difiiculties and disadvantages set forth.

The principle of the invention is founded on the observation that certain aromatic bodies having acid properties such as sulfanilic acid when added to an aqueous hydrogen peroxid solution, prepared in any way, renders the same stable, the addition of very small quantities showing surprising results as to stability, for example, the addition of 2 parts per thousand of sulfanilic acid to a 3% aqueous hydrogen peroxid solution .(one part by weight 30% 11,0 and nine parts distilled water), after 12 weeks shows no loss in-percent-age of the hydrogen peroxid, while without such addition after 3 Weeks 92.3% of the hydrogen peroxid is lost, after 4 weeks 99% of it is lost and after 12 weeks it is all lost.- The action of the sulfanilic acid .is also efiective for aqueous solutions of hydrogen peroxid of any other concentration and I do not restrictmyself to the degree of concentration set forth on to any specific proportion of sulfanilic acid to be used, various proportions of sulfanilic acid producing the results set forth when added to hydrogen peroxid solutions of various degrees of concentration.

What I claim and desire to secure by Letters Patent is:

OTTO QLIEBKNECHT.

Witnesses JEAN GRUND, CARL GRUND.

- 70. A hydrogen peroxid solution containing 

